Commonly owned U.S. Pat. Nos. 5,080,032; 5,129,343 and 5,231,946 disclose a monohull fast ship able to transport up to ten thousand tons of cargo at an average speed of 37 to 45 knots across the Atlantic Ocean in about three to four days in sea states up to 5, with a 10% reserve fuel capacity. The disclosures of these commonly owned U.S. patents are hereby incorporated by reference. While the high speed of these ships reduces the time for crossing the ocean, the efficiencies of transport of cargo by sea are effected not only by the speed of a ship but also the time to unload and load a ship in port before the ship can begin another transit. Prior art loading systems requiring cargo to be loaded from the top of the ship can require a time in port of one and a half days for loading and unloading.
Commonly owned U.S. Pat. No. 5,832,856, also hereby incorporated by reference, discloses a monohull fast ship with improved loading mechanism wherein a train of self-propelled trolleys are conveyed along one of rail pairs on the cargo carrying deck of the ship to decrease loading time in port from one and a half days down to six hours. However, the loading mechanism necessitates the use of docking facilities with rails to accommodate the trolleys moving to and from the ships and makes no allowance for meeting port/shipper security requirements. Additional time in port can be required for container inspection etc. to meet security requirements at the port and onboard the ship before putting to sea. There is a need for an improved system for rapid, secure transport of cargo by sea which allows the time in port for unloading and loading the ship and meeting security requirements to be further reduced and which permits the ship to be loaded and unloaded at docking facilities without rails. The present invention addresses this need.
A system of the invention for rapid, secure transport of cargo by sea comprises, in combination, an improved ship of the invention and an improved arrangement of the invention for loading and unloading cargo from the ship. Like the ship of Assignee's aforementioned patents, the ship of the present invention includes a hull producing a high pressure area at a bottom portion of a stern which rises from a point of maximum depth forward of a longitudinal center of the hull to a point of minimum draft at a transom which produces hydrodynamic lifting of the stern at a threshold speed above a length Froude Number of 0.40; sides of the hull at the datum waterline are non-convex in plan view with reference to a centerline of the ship; a length-to-beam ratio at the datum waterline is between 5 and 7.5 and a displacement to length ratio equal to a displacement of the hull divided by a cube of the length divided by 100 during operation of the hull in carrying fuel and payload is between 60 and 150 and a maximum operating Froude Number is between 0.42 and 0.9; a weather deck enclosing a top of the hull, at least one cargo carrying deck disposed below the weather deck and having a driving surface for self propelled, automatically guided vehicles transporting cargo to and from the ship through an opening in the stern of the ship and at least one lower deck disposed below the at least one cargo carrying deck; at least one water jet disposed within the hull with each water jet having an inlet in a bottom portion of the stern which produces high pressure during motion of the ship; and at least one power unit disposed on one of the at least one lower deck coupled to the at least one water jet for powering the at least one water jet to cause water to be drawn into the inlet of the at least one water jet to produce forward motion of the hull.
The improved arrangement of the invention for loading and unloading cargo through the opening in the stern of the ship and along the driving surface of the at least one cargo carrying deck includes at least one self-propelled, automatically guided vehicle for carrying cargo to be transported during loading and unloading of the ship, and a self-contained security scanning system on the at least one vehicle for maintaining control and surveillance of cargo in transit on the vehicle. Thus, the system is able to meet the recent substantial increase in the need for accurate security and tracking of containers and monitoring of their contents and of other cargo units at all times that the containers or cargo units are in transit on the vehicle during loading and unloading. This increase in security and tracking can reduce the time taken in port to load and unload containers/cargo units and process them through port security systems which necessarily depend upon random checks. The use of at least one self-propelled, automatically guided vehicle for carrying the cargo also eliminates the need for the use of rail pairs on the dock and in the ship. Because the vehicles in the disclosed embodiment move on rubber-tired wheels, without the need for rails, the ship can be loaded and unloaded at any normal roll on/roll off port. This reduces the effect of having to change port in the event of port closure by strikes or malfunctions of port facilities. It increases the flexibility of operations between different ports, rather than being restricted to those with specially installed rail systems of the prior art. These and other features of the invention make possible reduced in port time as discussed below, and provide an improved system and method for rapid, secure transport of cargo by sea.
The self-contained security scanning system on the at least one self-propelled, automatically guided vehicle of the arrangement for loading and unloading cargo according to a disclosed embodiment of the invention includes a reader and a field unit on the vehicle. The reader is capable of reading identification means, such as a tag unit, on a container/cargo carried by the vehicle and in turn communicates with the field unit. The field unit communicates with at least one of a ship server, a dockside server and a global data center.
The improved ship of the invention in the disclosed embodiment includes a reader grid having a plurality of readers in different, spaced locations along the at least one cargo carrying deck for reading the identification means on the cargo on the deck and for communicating readings of the individual cargo identification means to a ship communication system. Thus, once cargo with identification means is loaded on the deck of the ship by the automatically guided vehicle, surveillance of the cargo can be handed off from the automatically guided vehicle to the reader grid of the ship and the vehicle returned to the port dock. In the disclosed embodiment the ship communication system includes a ship server which communicates with global and local information centers, a super base on each cargo carrying deck which is linked to the ship server, and a plurality of a base stations on each cargo carrying deck communicating with respective ones of a plurality of groups of readers of the reader grid on the cargo carrying deck.
Guidance means are provided on the at least one cargo carrying deck of the ship for cooperating with guidance equipment of the at least one self-propelled, automatically guided vehicle carrying cargo for guiding the vehicle during loading and unloading the ship. The guidance means includes at least one of guide rails, electrical cable in grooves in the at least one deck in which different frequency signals are induced, and optical guidance means such as laser reflectors which cooperate with laser and optical scanning equipment on the vehicle.
The improved method for rapid, secure loading and unloading of cargo on a ship according to the invention comprises supporting cargo having identification means which can be remotely machine read on a self-propelled, automatically guided vehicle, transporting with the vehicle the cargo supported on the vehicle through an opening in the stern of the ship and along a driving surface of a cargo carrying deck of the ship, and reading the identification means on the cargo during the transporting with a self-contained security scanning system on the vehicle. As described above, in the disclosed embodiment the method further includes communicating the reading of the identification means from the vehicle to at least one of a ship server, a dockside server and a global data center. In addition, further reading of the identification means on the cargo is performed when the cargo is on the cargo carrying deck of the ship using a reader of a reader grid along the deck which communicates the further reading to a ship communication system thus handing off monitoring of the cargo/containers. This monitoring can continue within the ship at sea, the automatically guided vehicles being guided from the ship and remaining at port for loading and unloading the next ship in port.
Further features and advantages of the present invention will become more apparent from the following detailed description of an example embodiment of the invention taken with the accompanying drawings.